The feeding, fecundity and mortality of Liriomyza trifolii (Burgess) on the chrysanthemum cultivar 'Kyura-Kids' were determined in no-choice experiment and were compared with those on three other cultivars. There were no differences among cultivars in numbers of puncturing females, oviposition females and fertilized egg oviposition females. Number of feeding punctures, number of eggs laid and number of hatched larvae were not different among four chrysanthemum cultivars, while number of pupae fed on 'Kyura-Kids' were extremely small among them. This indicated that the resistance to L. trifolii of 'Kyura-Kids' reported on the basis of the field experiment was caused by high larval mortality.

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To clarify the characteristics of dry matter production in selective breeding line of Japanese wild radish, we carried out a study using three cultivars 'Taibyosoubutori', 'Karamaru' and the selected line of Japanese wild radish. The storage root of Japanese wild radish grew slowly. In the Japanese wild radish, total or shoot dry matter weight and dry matter ratio of root were higher, and root dry matter weight was lower than that of 'Taibyousoubutori' at harvest in December 2008. As a results, there were significantly differences in T/R ratio between the selected line and other cultivars. A higher leaf photosynthetic rate was obtained in Japanese wild radish at high light intensity. Our results suggest that Japanese wild radish has a higher source capacity and lower sink capacity in comparison with other cultivars, and the characteristics of dry matter production and sink-source balance of the selected line were largely different from 'Taibyousoubutori'.

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In this study, fungal growth of Aspergillus oryzae on potato dextrose agar (PDA) medium incubated under various temperature conditions was investigated. Each colony diameter was fitted well by a linear model and the calculated parameters of maximum growth rate and germination time were subjected to secondary models. Results indicated that maximum growth rate agreed well with Ratkowsky square root model, and germination time agreed well with a new model expressed with thermal time. From these results, simple prediction method for colony diameter was developed using thermal time in duration of germination time, and growth rate that can be determined by Ratkowsky square root model in growth phase. In this study, measurements have been performed for A. oryzae that was subjected to combination of different temperature condition, and colony diameters of estimation were agreed well with those of observation.

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